Thread: Simple media type program

I'm having trouble getting this program to display output. Please tell me what is wrong with the code provided.

N is the number of media type associations and Q is the number of filenames and they will be given as two numbers on first line of input.

INPUT:
Following this are N lines, each containing a file extension and a media type, separated by a space. Finally, Q lines, each containing the name of a file.

OUTPUT:
For each of the Q file names, print on a line the media type of the file. If there is no matching entry, print "unknown" (quotes for clarity).

Sample Input

5 6
html text/html
htm text/html
png image/png
svg image/svg+xml
txt text/plain
index.html
this.file.has.lots.of.dots.txt
nodotsatall
virus.exe
dont.let.the.png.fool.you
case.matters.TXT

Sample Output

text/html
text/plain
unknown
unknown
unknown
unknown

import java.util.Scanner;
import java.lang.String;
class sumNQ
{
public static void main(String args[])
{
Scanner s=new Scanner(System.in);
System.out.println("enter N and Q :");
String NQ=s.nextLine();
Scanner snum = new Scanner(NQ).useDelimiter(" ");//for getting the number of file types n and number of filenames q
int n=snum.nextInt();
int q=snum.nextInt();
int sumnq=n+q; // sum of total number of lines in input
 
String[] strarr = new String[sumnq]; // array of strings with each element containing a line of input
int i=0;
while(i<sumnq)
{
strarr[i]=s.nextLine();
i++;
}
 
String[][] strN = new String[n][2]; // 2d array of strings containing filetype in first element and mediatype in second element of first dimension
for(int j=0;j<n;j++)
{
Scanner strarrstr=new Scanner(strarr[j]).useDelimiter(" ");
strN[j][0]=strarrstr.next();
strN[j][1]=strarrstr.next();
}
 
String res="";
for(int m=n;m<sumnq;m++) // for iterating filenames starting at index n of strarr
{
String stest=strarrAfterPeriod(strarr[m]);
for(int l=0;l<n;l++) // for testing filenames starting at n with filetypes starting at 0 of strarr
{
if(stest.equals(strN[l][0])) // comparison
{
res+=strN[l][1]+"\n"; // output string
}
else if(l==n)
res=res+"unknown\n";
}}
System.out.println(res);
}
 
public static String strarrAfterPeriod(String str) // for fetching the string after last period of filename
{
Scanner speriod=new Scanner(str).useDelimiter(".");
String sper=speriod.next();
while(speriod.hasNext())
sper=speriod.next();
return sper;
}}

I don't understand why your output does not include what is printed by this line:
System.out.println("enter N and Q :");

Can you post the FULL contents of the command prompt console from when you execute the code?
To copy the contents of the command prompt window:
Click on Icon in upper left corner
Select Edit
Select 'Select All' - The selection will show
Click in upper left again
Select Edit and click 'Copy'

Paste here.

To see what your code is doing, you need to add lots of printlns to print out the values of the variables as they change and to show the logic flow.